Apparatus and method for making preforms in mold

ABSTRACT

Apparatus and a method of preparing fiber preforms disperses fibers and binder on a forming support surface such that the materials are conditioned and then applied to the surface where the composite material solidifies. Reinforcing material, such as fiber, is mixed with binder, such as thermoplastic or thermoset materials, so that the materials adhere. Then, the adhesive mixture is dispersed in a controlled pre-determined weight ratio on the support surface where the mixture sticks to the support surface, cools and solidifies. The deposited mixture can be an open mat having interstices between fibers. The deposited mixture can also be shaped further into a final desired shape before complete solidification. This method eliminates the need for solvents and their associated problems. The process does not require a vacuum or plenum system to hold the reinforcing material in place. The preform can be made in any shape, including sections or asymmetric configurations and remain in mold while being processed to a composite molded article.

FIELD OF THE INVENTION

This invention relates to an apparatus and a method of making a preform,particularly for use in composite molded articles, and also compositemolded articles. The apparatus and the method especially relate tomaking a structural preform for use with polymeric materials.

BACKGROUND OF THE INVENTION

High strength polymeric materials are being increasingly used to replacetraditional structural materials, such as metal, in many applications.The polymeric materials have the advantage of lower weight and are oftenless expensive and more durable than metals. However, polymericmaterials tend to be much lower in strength than metal. Unless polymericmaterials are reinforced in some manner, they often do not meet thestrength requirements for metal replacement.

Thus, polymeric composites have been developed to meet such strengthrequirements. These composites are characterized by having a continuouspolymeric matrix within which is embedded a reinforcement material,which is usually a relatively rigid, high aspect ratio material such asglass fibers.

Such composites are typically molded into a predetermined shape, whichis in many cases asymmetric. To place the reinforcement material intothe composite, the reinforcement material is usually placed into themold in a first step, followed by closing the mold and then introducinga fluid molding resin. The molding resin fills the mold, including theinterstices between the fibers, and hardens (by cooling or curing) toform the desired composite. Alternatively, the molding resin can beapplied to the reinforcing fiber prior to molding. The reinforcing fiberwith resin thereon is then placed into a mold where temperature andpressure are applied, curing the resin to prepare the desired composite.

It is desirable to uniformly distribute the reinforcement materialthroughout the composite. Otherwise, the composite will have weak spotswhere the reinforcement is lacking. Thus, it is important to prepare thereinforcement material so that the individual fibers are distributedevenly throughout the composite. In addition, the individual fibersshould be held in place to resist flowing with the molding resin as itenters the mold, which would disrupt the fiber distribution.

For these reasons, reinforcement has been conventionally formed into amat outside of the mold. The preform mat is then placed in the mold andeither impregnated with resin to make the final composite article, orsimply heated and pressed to make a very low density composite article.The mat is generally prepared by forming the reinforcing fibers into ashape matching the inside of the mold and applying a binder to thefibers. In some instances, a thermosetting binder is pre-applied, andthen cured after the fibers are shaped into a mat.

In other methods, a thermoplastic binder is applied, so that in asubsequent operation the binder can be heated and softened and the matsubsequently shaped. This binder “glues” the individual fibers to eachother so that the resulting mat retains its shape when it is transferredto the mold for further processing. The binder also helps the individualfibers retain their positions when the fluid molding resin is introducedinto the mold. In some cases, a molding resin can alternatively beapplied to the reinforcing fiber prior to molding. The fiber with binderand resin is placed into a mold where temperature and pressure are thenapplied, curing the resin to prepare the desired composite.

Binders conventionally used have been primarily of three types, each ofwhich have various drawbacks. The predominantly used binders have beensolvent-borne polymers, i.e., liquids, such as epoxy and polyesterresins. The solvent-borne binders are usually sprayed onto the mat viaan “air-directed” method, and then the mat is heated to volatilize thesolvent and, if necessary, cure the binder. This means that theapplication of binder is at least a two-step process, which is notdesirable from an economic standpoint. Also, the use of solvents isencountered, which raises environmental, exposure and recovery issues.Dealing with these issues potentially adds significantly to the expenseof the process. The procedure is also energy intensive, as the entiremat must be heated just to flash off solvent and cure the binder. Thecuring step also makes the process take longer.

Use of the solvent-borne polymer binders is extremely messy. There arealso high maintenance costs associated with keeping the work area andthe screen on which the mat is formed clean. In this case, where thebinder may be low viscosity fluid, it tends to flow over and coat alarge portion of the surface of the fibers. When a composite article isthen prepared from a preform made in this way, the binder ofteninterferes with the adhesion between the fibers and the continuouspolymer phase, to the detriment of the physical properties of the finalcomposite.

A second form of binder is powdered binders. These can be mixed with thefibers, and then the mass formed into a preform shape, which is heatedto cure the binder in situ. Alternatively, these binders can be sprayedto contact the fibers. However, simply substituting a powdered binder inan air-directed method raises problems. For example, powdered binderscannot be applied unless a veil is first applied to the screen toprevent the binder particles from being sucked through. Again, this addsto the overall cost and adds a step to the process. Airborne powders mayalso present a health and explosion hazard, depending on conditions ofuse. The use of powdered binders additionally requires a heating step tomelt the binder particles after they are applied to the fibers. Heatingrenders this process energy-intensive.

Binders of a third type are heated thermoplastic materials, which can bemelted and sprayed as a binder. Use of these materials makes anysubsequent heating step unnecessary, since the binder does not requireheat to achieve some undetermined measure of adhesion to the fibers.This method has problems with “lofting,” or inadequate compaction of thepreform. Lofting typically occurs because the thermoplastics areconventionally heated to any random temperature above their meltingpoints, leading to a lack of uniformity in their cooling patterns andextensive migration along fiber surfaces. This allows some of the fibersto “bounce back” before they are set into place by the solidifyingthermoplastic. This may result in formation of a lower density preformthan desired, density gradients throughout the preform, and pooradhesion of the fibers to each other.

In view of the problems discussed herein, one prior art method disclosedin U.S. Pat. No. 6,030,575, which is incorporated herein by reference,applies a heated binder to fibers already supported on a support surfacewhile a vacuum is applied to the other side of the support surface. Bythis method, the fibers are held in place by the vacuum while the binderis applied at a high pressure by a spray device. This applicationapplies pressure to the fibers thus forming a solid reinforcingstructure. Upon application, and with the assistance of the air flowfrom the vacuum, the binder cools and solidifies into the desiredpreform shape. However, the application of the vacuum requiresadditional equipment in the form of a plenum arrangement and alsorequires additional control functions and labor to properly apply thefibers and vacuum. Therefore, the material and operating costs areincreased.

In view of these prior art methods, it would be desirable to provide asimpler apparatus and a method for making preforms in which the problemsassociated with using solvent-borne, powdered or thermoplastic bindersare minimized or overcome. It would also be desirable to provideapparatus and a method in which sagging, slumping, and separating ofperform materials from tall vertical or nearly vertical surfaces isavoided. It would also be desirable to provide a lower cost method thatis simple to operate and thus more conducive to automation. In a moresimple forming process, it may even be possible to eliminate the need totransfer the preform to a molding tool and/or eliminate the need toapply a vacuum to the forming surface.

SUMMARY OF THE INVENTION

An aspect of this invention provides an apparatus and a method in whicha high strength structural preform and composite molded article can bemade efficiently and at a lower cost.

Another aspect of this invention provides an apparatus and a method ofmaking a preform and/or a composite molded article that does not requirethe use of an additional amount of organic solvents.

A further aspect of this invention provides an apparatus and a method ofmaking a preform and/or a composite molded article that can assume avariety of shapes, including asymmetric parts or portions of parts.

An additional aspect of this invention provides an apparatus and amethod that uses less components and thus reduces the capital entry andoperational production costs.

This invention can be easily adapted to automated production and/orcontrol.

A method in accordance with this invention comprises the steps ofproviding reinforcing material, providing binder material, mixing thereinforcing material and the binder material so that the binder materialadheres to the reinforcing material, applying a stream of the mixture toa support surface thereby adhering the mixture to the support surface,and solidifying the mixture to form the preform.

In particular, the method relates to making a preform for use in forminga structural part in which a stream of fibrous reinforcing material isprovided, particulate or liquid or atomized binder material is adheredto the reinforcing material by providing a stream of binder materialinto the stream of fibrous reinforcing material in a venturi to form anadhesive mixture, and the adhesive mixture of the reinforcing materialand the binder material is thermal sprayed against a support surface,optionally sequentially cooled by applying cooling media to the justthermally sprayed and deposited adhesive mixture, such that the mixtureadheres to the support surface and solidifies into the preform.

Preforms and composite molded articles made in accordance with themethod and its variations described herein are also encompassed by thisinvention.

It is to be understood that the invention described herein can be variedin a number of ways and is not restricted to the particular embodimentsdescribed herein. The invention is intended to generally include anyembodiment in which the fiber and binder material is combined prior toapplication to the surface where it then solidifies in the desiredshape.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be described in greater detail in conjunction withthe following drawings wherein:

FIG. 1 is a schematic perspective view of an end effector depositing thematerial onto a surface to make a preform in accordance with an aspectof this invention;

FIG. 2 is a schematic perspective view of a preform being made inaccordance with an aspect of this invention;

FIG. 2A is an enlarged partial section of one type of forming surfacefor use with the method in accordance with the invention;

FIG. 2B is an enlarged partial section of another type of formingsurface for use with the method in accordance with the invention;

FIG. 2C is an enlarged partial section of another type of formingsurface for use with the method in accordance with the invention;

FIG. 2D is an enlarged partial section of a preform formed by a methodin accordance with the invention;

FIG. 3 is a partial side view of an end effector for use with anembodiment of the method in accordance with the invention;

FIG. 4 is a partial perspective view of an end effector of FIG. 3;

FIG. 5 is a partial side perspective view of an end effector for usewith an embodiment of a method in accordance with the invention;

FIG. 6 is a partial perspective view of an end effector showing providedwith elements for applying a curtain of cooling media;

FIG. 7 is a partial end view of an end effector and the arrangement forproviding a curtain of cooling media;

FIG. 7A is a cut away in cross section of a pair of venturi apparatus;

FIGS. 8 and 8 a and FIGS. 8 c and 8 d are respectively a partial view ofa chopper gun assembly mounted on an end effector of FIG. 6 and apartial view of a chopper gun detached from an end effector of FIG. 6;

FIG. 9 depicts an end effector with heaters in operation to generate aheating zone and a mixture of reinforcing fibers plus binder streamingthrough the heating zone;

FIG. 10 depicts an end effector mounted on a robotically controlled armbeing used in making a preform for a boat hull;

FIG. 11 photographically depicts a robotically controlled arm having anend effector being used in applying fiber/binder in to a gel coated moldtool;

FIG. 12 photographically depicts a boat hull preform, obtained in afirst mold tool after completing fiber/binder application according toFIG. 11;

FIG. 13 photographically depicts a boat hull preform in a first moldtool in which the perform is trimmed for subsequent fabrication to afinished composite molded article;

FIG. 14 photographically depicts a trimmed boat hull preform in asupported first mold tool with a matching second mold tool shown in anopen position, before initiating resin transfer molding to manufacture acomposite molded article; and

FIG. 15 illustrates the use of more than one end effector in thefabrication of a preform.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

This invention is described below with reference to formation of apreform for use in the marine industry to construct fiberglassreinforced articles, such as a motor box for a boat, a hatch, deck, decksection or a boat hull. However, it is to be understood that this is anexemplary embodiment only and that the method can be applied in variousapplications in which high strength structural members are used. Forexample, a preform made in accordance with the disclosed embodiments ofthe invention could be used in the automotive, aircraft, or buildingindustries or as a component of household goods, such as appliances.Further, although specific examples of materials are provided herein,any suitable material can be used.

As seen in FIG. 1, a preform making assembly 10 used to practice amethod in accordance with the invention includes a materials applicator12 that applies the preform material mixture 14 to a support surface 16to create preform 18. The term preform in this application is intendedto cover any structure used as a reinforcing insert or structuralsupport within a composite structural part, which is preferably, but notnecessarily, a molded part. Such a preform 18 can be used whileremaining in a mold. Preform 18 could be formed and either used whileremaining in its mold or placed within a closed mold or on an open mold(a tray or base, for example) to form the composite part. Alternatively,preform 18 could be used as a base structure having materials attachedor molded to it, thus acting as a skeleton or tray and eliminating theneed for a mold base or molding tool. Preform 18 can be any desiredshape. In its simplest form, it resembles a shaped mat.

Materials applicator 12 in FIG. 1, includes a robotically controlled arm20 with an end effector 22 that delivers the preform materials mixture14 to support surface 16. Preform materials mixture 14 can be applied byend effector 22 by any known application method, including for example,spraying, blowing, streaming, ejecting, laminating, or draping.

As seen in FIG. 1, support surface 16 can be any surface including anentire part shape or portions of a part. Support surface 16 can includesurfaces oriented in any plane. This method is particularly suited forapplying material to a vertical surface 24. FIG. 2, for example, shows apreform 18 shaped as an entire boat hull, which can serve as a freestanding structural base during molding. In this case, preform materialsmixture 14 applied to support surface 16 includes randomly orientedchopped glass fibers retained by a thermoplastic binder, as seen in FIG.2D.

As will be recognized, support surface 16 can be made of any suitablematerial, including fiberglass, metal or ceramic, especially materialsknown for use in molding tools. The surface can also be pretreated ifdesired. For example, if preform 18 will be used merely by compressingand heating the preform without additional molding steps, it may bedesirable to powder coat support surface 16. Also, surface treatmentsused for molding can be employed, such as a gel coat, mold releaseagent, peel shell or veil, used alone or in various combinations.Obviously, the intended use of preform 18 can dictate the preciseconfiguration of support surface 16.

FIGS. 2A-2C show variations of support surface 16 usable with the methodin accordance with embodiments of the invention. Support surface 16 canbe a perforated plate-like member 26 with apertures 28, as seen in FIG.2A, which allows air to flow through apertures 28 in member 26 duringapplication. Although, as described below, there is no controlled airflow at support surface 16, ambient air trapped between support surface16 and mixture 14 during application can escape through apertures 28,thus providing more control during application of mixture 14 and a morecompact preform 18.

Alternatively, support surface 16 can be a stiff mesh 30 as seen in FIG.2B. In this embodiment, mixture 14 can adhere to mesh 30 and integratemesh 30 into the preform structure, thus adding rigidity. Mesh 30 alsohas the additional advantage of allowing ambient air to flow through itsapertures during application of mixture 14. Mesh 30 can be any suitablematerial, including fiberglass, plastic, metal, wood or any combinationthereof. Mesh 30 offers advantages during subsequent molding byproviding interstices into which later applied resin can flow and bind.

FIG. 2C shows a third type of support surface 16 suitable for thismethod. In this case, support surface 16 is a solid plate 32. A solidplate surface 32 is also shown in FIG. 1 in which a preform for a partis being formed. Mixture 14 directly adheres to plate 32 duringapplication. This variation can result in a compact preform structure 18as mixture 14 is pressed onto plate 32. Also, in this case, solidifiedmixture 14 can have a smooth outer surface for later treatment.

Support surface 16 also does not need to be shaped into the finaldesired shape of preform 18. Because mixture 14 is applied while tackyor viscous, by controlling the applied viscosity, mixture 14 can bepressed into a different desired shape than support surface 16 beforesolidification. This allows a large degree of flexibility in preformshapes as preform 18 is not restricted to the shape of support surface16.

Any suitable materials can be used to create preform 18. The reinforcingmaterial can be any material suitable as use as reinforcement.Preferably, the reinforcing material is a relatively rigid, high aspectratio material. In a preferred embodiment, the material is a choppedfibrous material such as fiberglass, aramid fiber (Kevlar brand fiber),high molecular weight polyolefin such as ultra high molecular weightpolyethylene (UHMWPE), carbon fiber, arcylonitrile fiber, polyesterfiber or a combination of any thereof. The material can be provided as achop, or it can be chopped during or just prior to the applicationprocess. It is preferable that the reinforcement provides a surface withinterstices so that subsequently applied molding material can closelybind with the reinforcement.

In the various described embodiments, fibrous reinforcement cut orchopped sufficiently for deposition via an effector 22 may be preferred.It should, however, be understood that a continuous fiber deposition canalso or additionally be accomplished in accordance with the presentinvention. By appropriate programming of a robotic arm 20, a suitableend effector 22 can deposit a continuous fiber on a surface 16 in apattern (swirls, loops or other pattern) or orient continuous fiberduring deposition in order to provide certain properties to a preformand to a composite molded article made from such a preform. Forinstance, a continuous fiber pattern can be laid from bow to stern whenmaking a preform for a boat hull, and/or can be laid transverse acrossthe beam (port to starboard). The fiber thus laid can be continuous inthe pattern or a chopper can be programmed to cut fiber discretely as anend effector 22 reaches a designated point as it traverses across asurface 16. It will also be appreciated that in principle a chopper,such as a chopper device 44 or a chopper gun in FIGS. 8 a-d, can beprogrammable and thus controlled to permit an end effector 22 to switchfrom depositing a mixture of chopped fiber/binder to depositingcontinuous fiber (fiber or fiber plus binder) and so on as a preform isfabricated in a mold.

The binder can be a commercially available particulate binder material,including thermoplastic and thermoset polymers, cellular andnon-cellular polymers, glasses, ceramics, metals, or multi componentreactive systems. One type of suitable binder, for example, is athermoplastic epoxy hybrid. Preferably, the binder is a true solid orsupercooled liquid at the ambient temperature prevailing during use sothat volatile organics such as solvents are not present in significantamounts. By this, environmental problems associated with solvents can beavoided. Further, the binder is preferably a material that does not needpost heat treatment for curing, thus reducing time and energyrequirements. The particular material can be any known binder,preferably one that can be conditioned, and/or melted withoutsignificant decomposition, adhered to reinforcing material upon cooling,and durable at temperature ranges typical in molding. A binder can beformulated to include a rubbery component or be rubbery binder toprovide toughness to the preform and composite molded article therefrom.A rubbery component can also be added separately from the binder and/orseparately from fiber. Suitably rubbery components include, forinstance, nitrile, urethane or a thermoplastic, preferably as suitablysized particulates. Although a single polymeric binder can be used, ablend is preferred when the deposited material needs to adhere well on atall vertical or tall nearly vertical surface because adhesion isimproved, especially when a curtain of a cooling media is passed overdeposited material (fibers and binder blend). In the various describedembodiments, the binder can advantageously be a mixture or combinationof binders. A commercially available polyester type binders, such asStypol® brand polyesters such as grade 044-8015 (Cook Composites andPolymers), becomes tacky after heat is applied in a heating zone fromburners and can exhibit good initial adherence to a surface. A hybridbinder, such as a blend of epoxy and polyester binder ingredients, canbecome tacky quickly and, when subjected to a cooling media after beingdeposited on a surface, surprisingly can exhibit a comparatively quickerset, stiffness and rigidity to maintain the fiber in place when afiber/binder mixture is applied as deposited material on a vertical ornearly vertical surface. An exemplary binder blend may incorporate anepoxy based thermoplastic granular powder (50-100 mesh, <35% fines)having relatively high molecular weight, softening point approximately75-80 C, with suitable polyester or also in combination a lowermolecular weight pulverulent epoxy (50-100 mesh, <35% fines) having ahigher softening point approximately 90 to 95 C, with the latter beingmore soluble in a solvent than the former epoxy. Suitable epoxies areavailable from Dow Chemical. In principle, suitable combinations ofbinder constituents can be chosen based on reactivities, Tg, and thelike known in the powder coating industry. In one of the preferredembodiments, about 10 wt. % binder relative to glass fibers (cut,chopped etc.) is used. In a further aspect of one of the preferredembodiments, the 10 wt. % binder comprises, as a hybrid binder, a blendof about 3:1 polyester:epoxy. The ratio can be adjusted to suit specificapplication requirements. The particular binder can be selected based onthe desired characteristics of the preform and its ultimate intendeduse. The density of the perform can be controlled by the length of fiberchop or combination of fiber lengths applied, the amount of binder andthe layer or layer(s) of fiber/binder applied, and/or by whether or notthe perform is subsequently compressed.

It will be appreciated that a variation of the described embodiments inwhich an end effector 22 deposits what may be termed a “pre-preg” on asurface 16, which may be a mold surface in mold tooling, is also part ofthe invention. In this embodiment, the amount of fiber reinforcement andresin deposited via an end effector 22 can include higher quantity ofbinder(s). For instance, in a pre-preg type embodiment, the binder(s)can be in an amount ranging up to approximately 20 to 30 or even up to40% of the deposited material on a surface 16. The fiber reinforcementcan constitute approximately the remainder, but is preferably depositedin higher lofted condition upon deposition for certain end uses. Higherlofting can be achieved by using longer cut or chopped fiber lengths, ora higher percentage of longer lengthed fiber reinforcement.

In principle, in these and the other embodiments, other materials can beintroduced into an end effector 22 to be applied to a support surface16. For example, a preform having potential electrical conductivity canbe prepared by incorporating a powdered metal, carbon powder, or even anelectrically conductive polymer in the reinforcement stream, the binderstream or by a separate stream. Flame retardant materials, for example,can be applied when forming a preform. The additional optional materialscan be incorporated in the mixture as applied to the surface 16. Ofcourse, if desired the other materials can be applied separately to asurface 16 (such as a prepared surface of a mold tool) apart from afiber/binder mixture supplied end effector 22.

An exemplary type of suitable end effector 22 is shown in FIGS. 3 and 4.End effector 22 is any element that can deliver material in accordancewith the method and its variations disclosed herein. End effector 22 ispreferably carried by robotic arm 20, but obviously could be manually orotherwise supported. In this method, a dual heat element configurationis employed. As seen in FIG. 3, a balanced split supply header 33,preferably natural gas, feeds two burners 34 and 36. The balanced header33 splits a main header to allow common feed to burners 34 and 36 tomaintain uniformity and equity of gas mixture supply and inlet pressureconditions in-process. Although not shown, an end effector 22 preferablyincludes a manifold (sometimes referred to as curtain generating anddirecting device) capable of providing a curtain of cooling media, suchas air or a non-ignitable gas, to material 14 deposited on a surface 16as the end effector 22 passes across the surface 16.

Each burner 34 and 36 has a burner ignition element 38 and 40,respectively, which could be capable of program driven ignition ormanual remote control. Other burners described herein can be similarlyignited and controlled. As will be described below, the dual burnerconfiguration creates a heat envelope or zone 42 within the flamesthrown by burners 34 and 36.

Preferably, burner(s) 34 (36), for example, provides a controlled,variable and even temperature profile with a nominal capacity of about10,000 BTU per lineal inch of burner. Burner(s) 34 (36) can include asupplied gas mixture control cabinet with sensors that continuallymonitor and correct flame mixture quality and oxygen content. Thus,flame quality can be controlled within predetermined limits. Automaticshutdown can be provided when the specified parameters are exceeded orif unsafe mixture conditions occur. The use of natural gas is preferredfor cost and efficiency, but any fuel could be used. A low pressureflame or, in principle, a hot air stream, can also be employed. Forexample, the flame velocity can be around 1000 feet per minute. Ofcourse, any number of burners or other suitable heat source(s) could beused depending on the desired size and configuration of heating zone 42.

Reinforcing material is provided by material chopping device 44.Chopping device 44 can vary depending on the type of material beingchopped. Chopping device 44 may be fully integrated with the processcontrol system to allow in-process start, stop, and run parameteradjustment based on control program requirements or process sensors andcontrol system signals from process monitoring. Chopping device 44 mayalso be manually controlled or varied by operator input. It is alsopossible to use pre-chopped material or other particulate material ifdesired. A chopping device, such as a chopping gun, in this or otherembodiments herein can provide chopped fiberous reinforcement in morethan one length, i.e. a quantity of chopped fibrous reinforcement of acertain length and another quantity of chopped fibrous reinforcement oflonger or shorter length.

Chopped material 46 is fed through material shape tube 48. Choppedmaterial 46, also called “chop”, can be blown, dropped, ejected orotherwise expelled from tube 48. Tube 48 is designed to provide adiscrete controlled area for material processing in preparation forintroducing chopped material 46 into the material stream. It can alsoprovide a controlled volume for any material conditioning medium thatmay be desired. As seen in FIG. 3, chopped material 46 is fed in astream toward heating zone 42. An air inlet 50 is provided in tube 48 toassist in shaping or orienting the stream of chopped material 46 as itis expelled from tube 48.

Binder introduction ports 52 and 54 deposit binder 56, in the form ofstreams, toward heat zone 42. Ports 52 and 54 are preferably designed tointroduce air conveyed binder from a metered dispensing unit into thematerial stream. Binder 56 can be in the form of particulate or anyconventional form that can be mixed in with chopped fibers 46, as notedabove. In this arrangement, binder 56 is presented as dual streams thatare interspersed into the flow of chopped fibers 46 prior to enteringheat zone 42.

An alternate end effector assembly is shown in FIG. 5, in which an endeffector 60 is mounted on robotic arm 20. In this arrangement, a centralburner element 62 is provided with a single burner ignition element 64and a burner face 66. A pair of reinforcement material chopping devices68 and 70 are positioned on either side of burner element 62 and deliverstreams of chopped fiber 46 toward a focal point in heat zone 42 thoughdelivery tubes 72 and 74, respectively. Four binder introduction ports E(reference numbers 76, 76 a, 78, and 78 a) are provided adjacent toreinforcing material delivery tubes 72, 74 to deliver streams of bindertoward the focal point). By this, streams of reinforcing material 46 andbinder 56 can be layered together into the heating zone 42 to mix thematerials and create an adhesive mixture. Although not shown, an endeffector 22 preferably includes a manifold (sometimes referred to ascurtain generating and directing device) capable of providing a curtainof cooling media, such as air or a non-ignitable gas, to material 14deposited on a surface 16 as the end effector 22 is directed or passedacross the surface 16.

Alternatively, binder 56 can be conditioned by a conditioning device,such as a heater, prior to being introduced into the stream ofreinforcing material 46. In this case, no heat zone would be necessary,which would eliminate the gas control cabinet and controls, independentmetered binder feed unit, burner supply header, and the ignition andburner elements. Such a binder heater could heat treat the material andthen blow air across the surface to eject heated binder particles.

In operation, the particular end effector could vary provided thatreinforcing material 46 is delivered to a zone in which heated binder 56can be mixed therewith. The mixing causes the materials to adhere intoan adhesive mixture 14. Adhesive mixture 14 is then deposited ontosupport surface 16 where it solidifies into preform 18. Use of differentend effector arrangements allows different properties to be achieved.Using different numbers of streams or layers of reinforcing material 46and binder 56 will vary the final preform properties. Similarly, mixingbinder 56 after it is heated, before it is heated or while it is beingheated will vary the final properties of preform 18.

As depicted in FIG. 6, another suitable end effector 22 includes venturi80 that have a generally centrally located port 81 through whichreinforcement, chopped fiber glass, carbon fiber or the like, isintroduced. The binder is delivered into a venturi through port 100, cancoat the reinforcement streaming through the venturi 80 and togetherwith the reinforcement is expelled by a carrier gas from the venturi 80through a nozzle 84 in a spray pattern.

As shown in FIGS. 6 and 7, opposing burners 85 and 86 are preferablycanted inwardly at a slight angle relative to one another. In operation,the flames from burners 85 and 86 are preferably not parallel to astream of binder and reinforcement expelled nozzle 84 so that as thestream exits a nozzle, it will pass through a heating zone created bythe flames from burners 85 and 86. This zone is similar to zone 42 (FIG.3 and FIG. 4). This is also shown in FIG. 9.

As described above, an end effector 22 is preferably, operativelypositioned at a distance from a surface 16 (not shown) in order toachieve a consistent deposit of binder/reinforcement (“depositedmaterial) on the surface.

With a surface 16 that includes a relatively vertical portion, verticalportion, or portion having complex curvature or arc, such as a side of aboat hull or vehicle body part, material 14 (from the stream of bindercoated fiber) initially sticks to such surface. The deposited material14 can, however, sag, slump or slough off such vertical portions(sometimes called sections or regions), such as sections of boat hullsor vehicle parts. A cooling curtain can overcome the above problem. Agaseous cooling media, such as an air curtain, from balanced manifolds88 and 88 a (FIGS. 6, 7, 8 and 9), is applied to the fiber/bindermixture deposited as an end effector 22 traverses over a surface 16 orover a previously deposited layer on a surface. The cooling provided issuch that the binder may be induced to more quickly set, or at leastmore completely partially cure, so the deposited material can retaininternal rigidity, shape and position on a vertical portion, nearlyvertical portion, or a highly complex curved portion of a surface 16.Steeply sloped portions of a surface 16 also advantageously receivedeposited material with subsequent cooling from a cooling curtain asdescribed above. As shown in FIGS. 6 and 7, manifolds 88 and 88 a caninclude a guide element 89 to help direct the cooling media to thesurface 16 while minimizing potential interference with the heating zoneestablished by the flames from burners 85 and 86. The guide element 89also helps avoid accumulation of fibers and stray binder fromaccumulating on and potentially clogging the manifolds 88 and 88 a. Themanifolds, e.g., cooling curtain generating and delivering devices,provide a gaseous cooling media that can, if desired, be pre-cooled orconditioned. The gaseous cooling media can be air or an inert,non-ignitable gas such as nitrogen. An air curtain can alsoadvantageously entrain surrounding atmosphere as it flows towards asurface 16 to thereby increase the overall volume of cooling mediaapplied. The cooling media supplied via manifolds 88 and 88 a ispreferably subject to process controls that regulate, for instance, therate, amount, pressure, duration, and interruption in the supply orapplication of the cooling media.

As shown in FIG. 7A, venturi 80 can include a port 100 for introducingbinder, a fiber port 81 (sometimes referred to herein as an inlet) forintroducing fiber (cut fiber glass, carbon fiber, polyester fiber,acrylonitrile fiber, aramid fiber (Kevlar brand fiber), and/or HMWPE,chopped or cut to a desired length(s)), a port 102 for introducing apressurized carrier gas, and nozzle 84. By present preference, inoperation, the binder is delivered through a binder inlet 100,preferably into approximately the center of a fiber stream before theconstriction in the central passage way of venturi 80. Due to theventuri effect, venturi 80 can pull the fiber reinforcement from a fibersource, such as chopper gun operatively connected to venturi 80, thefiber and binder are admixed in venturi 80, and then propelled(expelled) from venturi 80 through nozzle 84 by the carrier gas. Theexpelled material passes through a heating zone to be heated on its waytowards the target surface, which can be a prepared surface of a moldtool. In this embodiment, a heating zone can be formed downstream of thefan nozzles 84 about a region where flame from the burners 85 and 86 isthrown. The adhesive mixture of fibers/binder passes through the heatingzone (FIG. 9). Presently, a separate carrier gas stream is preferablyused and is introduced through port 102. However, variations in venturidesign and operation are within the scope of the invention. Forinstance, the binder can also be introduced into venturi 80 through port102 with forced carrier media, such as ambient air or other suitablegas, and this carrier media can, if desired, be used as a carrier gasfor venturi 80. The fibers can also be pulled or expelled from a choppergun or fiber source by a carrier media, such as an air stream, into thefiber port 81. In either case, the carrier gas, its rate of flow, andthe like are preferably subject to appropriate process controls, such ascomputer controls, including flow regulators. An end effector 22 canhave one or more venturi 80 or another configuration of venturi 80. Aventuri 80 is an effective and efficient means for delivering anadhesive combination of fiber with binder through a heating zone beforebeing deposited on a surface 16.

The rate of media flow through venturi 80 out nozzles 84 is a parameteraffecting the dwell time of the fiber/binder mixture (sometimes calledmixture 14) in the heating zone 42 and thus the qualities of theperform. Accordingly, the velocity of gas flow through venturi 80 can bemonitored and controlled by suitable process controls when the endeffector 22 is in operation. Or, for instance, the flow rates can bemanually set, in which case the flow rate will be measured and dwelltime ascertained based on the flow rate through the heating zone. Thus,if a binder is introduced into venturi 80 with a binder carrier gas, thebinder supply can be shut off and binder carrier gas allowed to flowthrough venturi 80. Similarly, if fibrous reinforcement, or any othermaterial, is propelled into a venturi 80 with a gas, the fiber and allother material supply can be shut off and its carrier gas allowed toflow through venturi 80. The velocity of all “carrier gas” through theventuri 80 can be monitored and measured from which a dwell time in theheat zone can be calculated or estimated and the flow rate(s) setmanually or adjusted by process controls. The dwell time in heating zone42 establishes a thermal treatment suitable for the binder(s) in thefiber/binder mixture so that when deposited on the surface 16, such as amold tool, the fiber/binder mixture is at least more capable ofretaining its shape and position without undesired sagging, slumping andthe like. Inadequate dwell time can lead to poorly adherent depositedmaterials and thus an inferior preform. It will be appreciated that theparameters may, in principle, also be ascertained for a particularprocess combination by conducting appropriate test runs.

In FIGS. 8 a-8 d show an end effector of FIG. 6 in which guide elements89 are not installed with a chopped gun assembly. FIGS. 8 a and 8 bdepict end effector 22 in operative connection with a chopper gun andFIGS. 8 c and 8 d depict end effector 22 and a chopper gun separated toshow how they may be connected.

In FIG. 9 an end effector 22 on a robotic arm 20 is shown in which astream of material propelled through nozzle 84 passes through a heatingzone established by the flames from burners 85 and 86. The stream ofreinforcement and binder propelled from a fan nozzle 84 passes throughor by a heating zone established by the flame from the burners beforebeing deposited on a surface 16 (not shown).

End effector 22 on a robotic arm 20 can be controlled as shown in FIG.10 to apply (spray deposit etc.) fiber/binder in a pre-selected pattern.More particularly, FIG. 10 shows a robot arm 20 with an end effector 22being applied in a controlled pattern to form a preform in a first mold.The arrows depict an exemplary pattern of deposited materialcorresponding to the pre-selected traverse of end effector 22 over thesurface. The robot arm is preferably under process controls, such ascomputer programming or the like.

FIG. 11 illustrates a computer controlled robotic arm 20, an endeffector 22 (with air curtains), the flange 92 of a first mold tool 90,a skirt 91 about the exterior of the first mold tool 90. In thisembodiment, the first mold tool 90 can have a gel coat on the moldingsurface and, optionally barrier coat(s) and/or reinforcement layer(s)laid over the gel coat, before the fiber/binder is sprayed to form theboat hull preform 95 as shown.

FIG. 12 and FIG. 13 show, respectively, a preform 95 obtained aftercompleting the fiber/binder application with slight over spray ofmaterial (FIG. 12) protruding over the flange 92 (not seen), and thetrimmed preform 95 a in the first mold tool 90 (FIG. 13) with the flange92 clear. In FIG. 13, the protective skirt 91 has been removed to show aportion of support structure 96 for first mold tool 90.

FIG. 14 shows a trimmed preform 95 a in a first mold tool 90 havingsupport structure 96 and in open relationship to matching second moldtool 90 a. The second mold tool 90 a can be closed, e.g. clamped or bevacuum sealed, in operative molding relationship with first mold tool 90to define a mold cavity containing preform 95 a and resin can beintroduced into the cavity of the closed mold. A gantry or frame 99 witha lift capability is shown supporting mold tool 90 a in open, opposedrelationship to mold tool 90. Gantry or frame 99 can lower mold tool 90a to mold tool 90 to establish a closed mold. It will be appreciatedthat the gantry or frame may have extendible and retractable (or evenrotatable) armature support for mold tool 90 a to more readily permit,among other things, its spatial adjustment over a mold tool 90 prior toforming the closed mold tool. Mold tool 90 with a formed-in-placepreform 95 a (a boat hull) has been moved between work stations. Supportstructure 96 can include or be operatively connectable to a transportsystem 98 so that after preform 95 a is prepared in a work station, itcan be transported while remaining in the mold tool 90 within thefactory to another work station and positioned in operative relationshipto receive other treatment, such as in this case being positionedrelative to mold tool 90 a. Transport system 98 includes rails as shown.It will be appreciated that other suitable apparatus for shifting workpieces (mold tools etc.) between different work stations in factory canbe employed as shown in FIG. 15. For smaller work pieces a manuallymovable apparatus for conveying a mold tool with preform from one toanother work station. It is in principle possible to have the gantry orframe 99 also on tracks or connected to other suitable transportmechanism to permit movement within a factory. It will be appreciatedthat the transport system or mechanism may also be process controlled.

FIG. 15 shows the surface 16 of a first mold tool 90 (not shown) and apair robotic controlled arms 20 and 20 a, end effector 22, and acarriage (roller as illustrated). Each end effector 22 can deposit thesame or a different fiber/binder mixture. By preference, each is alsoprocess controlled. Robotic arms 20 and 20 a can each more readilyextend their respective end effector 22 across a surface 16, such as amold tool 90, to a far side away from their respective base 20 b and 20c to more readily permit even deposition of fiber/binder to a respectiveopposing portion of surface 16, such as a mold tool 90, especially ifsuch opposing portion has a complex shape or steep portion.

As will be understood, preform 18 or 95 a can be used to fabricate acomposite molded article in subsequent processing using resin transfermolding (RTM), VARTM (vacuum assist resin transfer molding), compressionmolding process, structural-reaction injection molding (S-RIM), or, forinstance, in a vacuum infusion process. Heat and/or pressure moldingsteps can be employed in fabricating a composite article from a preform.

Of course, any suitable end effector 22 can be used, provided that theappropriate mixing and heat control can be employed. As can beunderstood from above, preform 18 or 95 a can be made with differentproperties by controlling, for instance, the heating zone, thetemperature of the binder, reinforcement and the degree to whichreinforcement fiber is chopped or cut, and the distance between endeffector 22 and support surface 16. For example, the material 14 or afiber/binder mixture as in FIG. 9 can be controlled so that the mixturehas sufficient tackiness when applied to support surface 16 so that itquickly solidifies. Alternatively, mixing can be controlled so that themixture applied (hitting) support surface 16 is sufficiently tacky toadhere to support surface 16 but remain moldable so that it can bepressed or further shaped.

As described herein, control of the various elements and parameters canbe manual or automated. If automated, a system can be provided usingknown programming techniques in a controller or processing apparatus,such as a microprocessor. Process control, especially robotic control,can be achieved by robot control signals, process sensor feedbacksignals, process material regulation, material selection and presetspecifications. These and other concepts are also embodied within theterm computer controlled, or the like. Programming packages arecommercially available that can be used to program a controller for arobotic arm 20 or chopper gun. Using process control for a robotic armhelps ensure correct orientation of end effector 22, attaining anoptimal concentration of fiber over surface 16 or other surface to whichthe material is deposited with minimal deviations and minimal variationbetween like-made preforms.

Although mentioned elsewhere, the parameters that affect preformfabrication include the level of control of the heat source or flame,the velocity at which the flame, binder and chop are introduced, theratio between these elements, and the distance of end effector 22 from asupport surface 16, which can be a prepared surface of a mold tool 90 or90 a as the case may be. For example, if a less viscous mixture isdesired, a binder can be selected that is less viscous when heated to ahigher temperature. By this method, application of adhesive mixture canbe controlled. Adhesive mixture also does not need to be applied at ahigh velocity and pressure. Because an adhesive mixture, such as amixture 14, adheres to support surface 16, it may be draped over asurface 16 (or mold tool 90) to achieve different qualities in a preform18 or preform 95 a.

As mixture 14 can stick to support surface 16 due, for instance, to theconditioning during the mixing operation, no additional methods ofholding the reinforcing material 46 in place are necessarily required.This eliminates the need for any vacuum or plenum assembly over themold. Further, since a low pressure flame velocity is used, the problemof blowing reinforcing material off of support surface 16 or todifferent places on support surface 16 is not present. Additionally,since mixture 14 can be closely controlled, different shapes andthickness of preform 18 can be achieved. However, as described herein,the adhesive mixture advantageously receives cooling from a gaseouscooling curtain, especially if the surface 16 is or has a tall verticalor near vertical section, such as the freeboard of a large boat hull.

Thus, it can be seen that the apparatus, the method and their variationsin accordance with this invention allows complicated shapes to be easilymolded directly on a forming surface, such as a mold tool, thussimplifying the process of making preform 18 or 95 a and also theultimate molding processes in which preform 18 or 95 a is used. Also, aone piece preform, even in large shapes such as boat hulls, can beformed using the preform without first removing the preform from itsmold tooling. This reduces labor costs and production time and canresult in a stronger composite part.

Preform 18 or 95 a formed in accordance with any of the aboveembodiments can be used in a molding process to make a compositestructural part. For example, preform 18 or 95 a may be used in a vacuummolding process in which resin is applied to preform 18 or 95 a with theassistance of vacuum and then the composite structure is cured.Alternatively, a molding material, such as resin, can be applied topreform 18 or 95 a and, then, heat and/or pressure can be applied toform the composite part. Also, simply heat and/or pressure can beapplied to preform 18 or 95 a to compress mixture 14 and form a part.The pressure can include reduced pressure in a vacuum bagging apparatus.The direct formation of a composite is particularly suited for thepre-preg embodiment. Pre-preg embodiment may find particular applicationin aerospace and non-civilian applications.

The present invention offers a composite part maker a cost advantageousprocess to apply fiber reinforcement directly into existing gel-coatedmold tool to fabricate a preform without having to remove the preformfrom its associated mold tooling in order to make the final compositemolded article. It will be appreciated that the preform can have ashaped surface corresponding to a desired shaped surface of the finishedcomposite molded article.

For example, a preform made according to this invention could be used ina molding process that includes the following steps. After the preformis solidified, the preform remains in its mold (or, is placed in asuitable mold) and a molding material, such as resin, is applied. A gelcoat or the like can, if desired, be formed first in the mold before apreform is placed in the mold. The mold can be an open mold or a closedmold. In the latter case, the molding tool would usually be closed priorto introduction of resin into the mold cavity. Then, after the mold iscompletely filled, the resin is cured. The article can then be removedfrom the mold and used in that state or further treated or shaped tosuit a manufacturing process. Before the introduction of the moldingmaterial, the preform could also be shaped prior to its completesolidification, cut, or heated and shaped to conform to desired moldingconditions. Additionally, separate preforms could be used together toform a structural base prior to molding.

More particularly, in a manufacturing embodiment, a boat hull, boat deckor other composite part can be prepared as follows. A first molding toolis prepared. Preparing the mold surface of the first mold tool caninclude cleaning and, as necessary, providing a coating of a releaseagent. The prepared mold tool can be gel coated. For instance, if asurface of a finished composite part formed by the first mold surfaceneeds to have a decorative or protective coating, a so-called powdercoating can be applied to the molding surface of the prepared firstmold. Or, such surface it can, if desired, be only primed. A gel coatingor powder coating may be omitted if no specific surface coating isrequired on either a preform or final composite. If a gel-coat isapplied, it is preferably allowed to cure. Barrier coats, as needed ordesired, can be applied over the gel-coat. If the first mold tool has asection, area or region having a tight radius or complex curvatures,fiber strands or air fluffed fiber strands, or strips of any otherreinforcement can be laid up, if desired, over any coating (gel coat orbarrier layer(s)) in the tight radius or on the complex curvature tominimize fiber bridging during later process steps. Shorter lengthfibers can also be applied with an end effector 22 into these tightcorners or complex curvatures to minimize fiber bridging. The first moldtool and its support (if support is provided) are positioned andfiber/binder are applied directly to form a mat of deposited materialonto the cured gel-coat preferably using at least one roboticallycontrolled device equipped with an end effector 22. The roboticallycontrolled device is preferably operatively equipped with an endeffector 22 having venturi 80 and cooling curtain means 88 and/or 88 a.The fiber/binder mixture, such as in FIG. 9 or mixture 14, can beapplied according to a selected pattern, such as shown in FIG. 10, asdeposited material and can be applied to form layer(s) in a mat offiber/binder. The mat preferably has open interstices between and amongfibers. Robotically applied material is preferably computer controlledto assure ready, repeatable fabrication of a particular preform design.For instance, fiber chop, binder feed, spray patterns, layering, flametemperature, cooling air (cooling curtain), and distance from thesubstrate are among the features that can be computer controlled. Itwill be appreciated, however, that the fiber/binder can be applied bymanually controlling an end effector 22, but this could introduceprocess variation and cause reduced consistency in both the process andin the finished composite structure. It will also be appreciated thatdifferent fiber materials can be applied by end effector 22 or aplurality of end effectors 22 in order to form differing layers orregions of a preform with different composite properties. For example,in a multi-layered preform, different layers can in principle havedifferent fiber reinforcement or different fiber orientation(s). Acarbon fiber layer can be applied on top of the e-glass layer to replacein whole or in part an engineered fabric that may otherwise be laid intothe mold tool during the process of fabricating a preform. Of course,application of carbon fiber alone, another fiber(s) alone, e-glass(fiber glass etc.) alone or any in combination is contemplated by ourinvention. Depending on the composite structure to be produced, otherengineered fabrics can be laid in as desired before, during, or afterthe fiber/binder are applied. It will be appreciated that inmanufacturing certain boat hulls or other marine composites, additionalstructural elements, such as stingers, bulkheads, flooring support, andthe like, can be introduced into the first mold as the preform is beingformed or afterwards. Such additional structural elements can be used todefine storage areas or, for instance, compartments in which a marinemotor or fuel tank can be installed. Stringers, bulkheads, otherstructural elements and the like, such as disclosed in U.S. Pat. No.5,664,518, the complete disclosure of which is incorporated herein byreference, can be used. Obviously, the preform fabrication method couldbe adapted to fabricate pre-glassed structural elements themselves.Closed cell shaped foam or other structural material can be laid in toprovide additional preform structure, such as a bulkhead, stringer etc.,even without being pre-glassed or pre-fleeced with fiber-reinforcement,preferably before the fiber/resin completely cures. The foam or otherstructural material can have a surface(s) prepared with adhesive orbinder compatible with the deposited material in a preform. Thefiber/binder application can be interrupted to permit installation ofadditional structural element(s), in which case the fiber/binderapplication can be resumed, as desired, to provide a layer(s) depositedover the added structural element(s) to make it an integral andrelatively seamless part of the preform. After a material is depositedon the surface, especially if the surface has a steeply sloped or a tallvertical section, an end effector 22 (FIGS. 6 and 7) having manifolds 88and/or 88 a (e.g., at least one cooling curtain means) applies a curtainof gaseous cooling media to the just deposited material to avoidsagging, slumping, sloughing off or other separation of the depositedfiber/binder from the surface or from another intervening layerdeposited on the surface. After the fiber/binder application iscompleted and cures, the preform obtained is trimmed as needed and theflange of a first mold tool etc. is cleaned as necessary. In a preferredembodiment, a closed mold system is used with the first mold tool beinga female mold and a second mold tool being a matching male mold whereinone or both of the first and second molds is closable with respect tothe other so as to define there between a mold cavity. Depending on themolding process, in a subsequent step resin can be injected or infusedinto the mold cavity. In manufacturing a boat, any conventional resincan be used, including thermoplastic resin. The resin cures, the mold isopened and the thus produced composite (boat hull in this example) isremoved.

It will also be appreciated that a composite structure, such as a boathull, can be prepared with a finished exterior exposed hull surface anda finished interior (deck, cockpit etc.) exposed surface. In thisembodiment, the general procedure can be the same as above but modifiedso that the molding surface of the second mold is coated with releaseagent, gel-coated or finish coated before it is closed with the firstmold tool and the resin is introduced into the cavity defined by theclosed mold tools. The second mold can be contoured so that the finishedcomposite can have the desired interior surface. In principle, thegeneral procedure can be modified further to fabricate a compositeformed from a preform in the first mold and a preform fabricated in thesecond mold. When the matching first and second molds are closed, theinjected or infused resin bonds the two preforms together. In this andother embodiments, the resin can, in principle, be foamable for use in aclosed or open mold application.

The use of an end effector 22 in accordance with the present inventioncan be combined with so-called zero injection pressure resin transfermolding (“ZIP RTM molding”). The latter molding process is generallydescribed in Composite Fabrication, pages 24-28 (March 2003), thecomplete disclosure of which is incorporated herein by reference. Forinstance, an end effector 22, preferably one with curtain(s) of coolingmedia and using a venturi for fiber and binder supply, can be used toform a layer(s) of fiber/binder instead of hand laying in the fiber matsand binder. Although vacuum can be applied to frames in a ZIP RTMmolding process, it is not a requirement in the present embodiment. Forinstance, a lower molding tool according to a ZIP RTM molding processcan be used as a first mold in this embodiment because it is similar toan open mold, but advantageously lighter mold tooling becomes feasible.

It will be appreciated that a composite structure can be prepared inwhich instead of a gel coating, a skin layer can be first formed in afirst mold and, optionally, one or more barrier layers (solid and/orfoamed) can be formed on the exposed surface of the skin layer, andfiber/binder layer(s) can be applied over the barrier layer(s) using anend effector 22 in accordance with the present invention. The remainderof the procedure can be conducted as described above. In a furthervariation of this and the other embodiments, all or part of the resinintroduced into the closed mold can be a foamable resin.

It will be appreciated that manifold 88 and/or 88 a can be selectivelycontrolled so as to supply a warmer or hot air curtain, if needed, orone can supply a warm or hot air curtain and the other a cooling aircurtain. In this variation, each manifold can be appropriately processcontrolled so that an air curtain of a selected temperature can beapplied.

Various parts can be made, as noted above, that are useable in themarine industry or other industries that utilize fiberglass reinforcedarticles. For example, partial hulls, boat decks in whole or part,hatches, covers, engine covers, marine accessories and the like may bemanufactured using preforms made in accordance with this process.Similarly, other marine vessels such as personal watercraft may bemanufactured with parts made from this process, including for example,engine covers, hulls in whole or part, hatches and the like. Parts madeaccording to this process would also be usable in the automotiveindustry to manufacture both interior and exterior components or bodyparts for vehicles. The use of such parts is not limited to vehicles assuch parts could be used in any structural article, such as a storagecontainer or construction component.

The complete disclosure of U.S. application Ser. No. 10/038,771, filedJan. 8, 2002 is incorporated herein by reference.

It is to be understood that the essence of the present invention is notconfined to the particular embodiments described herein but extends toother embodiments and modifications that can be encompassed by theappended claims.

1. A method of making a preform in a mold, said mold being adapted sothat said preform remains in-mold during subsequent processing to acomposite molded article, said method comprising: providing reinforcingmaterial; providing binder blend material; mixing the reinforcingmaterial and the binder blend material in a venturi mixer so that thebinder material adheres to the reinforcing material; applying a streamof the mixture from the venturi mixer through a heating zone to aprepared surface of a mold tool, said applying being conducted withoutuse of a plenum system; applying a stream or curtain of gaseous coolingmedia to the material on said prepared surface; and sufficientlysolidifying the mixture to form said preform in said mold, wherein saidpreform remains in said mold during subsequent processing to a compositearticle.
 2. The method of claim 1, wherein the step of applying a streamof the mixture includes spraying the mixture against the preparedsurface.
 3. The method of claim 1, wherein the step of providing thereinforcing material includes providing chopped fibers.
 4. The method ofclaim 3, wherein the step of providing the chopped fibers includesproviding chopped fiberglass.
 5. The method of claim 1, wherein the stepof providing the reinforcing material includes emitting a stream ofchopped fibers into said venturi mixer.
 6. The method of claim 1,wherein the step of providing binder includes emitting a stream ofbinder particulate into said venturi mixer.
 7. The method of claim 1,wherein the step of providing binder includes conditioning the binderbefore mixing the binder with the reinforcing material.
 8. The method ofclaim 7, wherein conditioning the binder includes heating the binder. 9.The method of claim 1, wherein the step of mixing the reinforcingmaterial and the binder includes a stream of reinforcing material and astream of binder and mixing the streams in a venturi mixer.
 10. Themethod of claim 9, wherein the mixed streams of reinforcing material andbinder are emitted from said venturi mixer and wherein said mixture isapplied so as to form a plurality of layers on said prepared surface.11. The method of claim 1, wherein said heating zone comprises applyingheat by forming a controlled heating zone and propelling the mixture ofreinforcing material and binder through the heating zone.
 12. The methodaccording to claim 12, wherein applying heat includes creating a flame.13. The method of claim 1, wherein an end effector apparatus is providedin operative, moveable relationship with respect to said mold, said endeffector apparatus heating elements to apply heat to form a heatingzone, having the venturi from which the mixture of reinforcing materialand hybrid binder are propelled through said heating zone to saidprepared surface, and elements to form and apply at least one curtain ofgaseous cooling media to said prepared surface.
 14. The method of claim1, wherein the step of applying the mixture to a prepared surfaceincludes applying the mixture to an at least vertically orientedprepared surface.
 15. The method of claim 1, wherein the step ofapplying the mixture to a prepared surface includes applying the mixtureto a solid prepared surface.
 16. The method of claim 1, wherein the stepof applying the mixture to a prepared surface includes applying themixture to a surface at ambient air conditions.
 17. The method of claim1, wherein the step of applying the mixture to a prepared surfaceincludes applying the mixture to a surface having apertures therein. 18.The method of claim 1, further comprising shaping the mixture afterapplication to the prepared surface and prior to solidifying.
 19. Themethod of claim 1, wherein the step of solidifying the mixture includescooling the mixture so that it conforms to the shape of the supportsurface.
 20. The method of claim 1, further comprising applying amoldable material to the preform to form a composite and curing thecomposite to form a part.
 21. The method of claim 20, further comprisingapplying a vacuum to the composite before the part is cured.
 22. Themethod of claim 1, further comprising applying at least one of heat andpressure to the preform to form a molded part.
 23. The method of claim 1further comprising adding resin to the preform prior to applying atleast one of heat and pressure to the preform.
 24. A preform formed inaccordance with the method of claim
 1. 25. A method of making a preformfor use in forming a structural part, comprising: providing a stream offibrous reinforcing material; adhering particulate binder material tothe reinforcing material by combining a stream of binder material to thestream of fibrous reinforcing material in a venturi device to form anadhesive mixture; and applying the adhesive mixture of the reinforcingmaterial and the binder material from said venturi through a heatingzone and against a support surface, optionally applying a stream ofgaseous cooling media to the material sprayed on said surface, such thatthe mixture adheres to the support surface; and solidifies into thepreform.
 26. The method of claim 25, wherein said applying said adhesivemixture comprises spraying and said method includes applying said streamof gaseous cooling media by passing a cooling air curtain over theadhesive mixture sprayed on the support surface.
 27. The method of claim26, wherein said spraying and said cooling occur in the absence of aplenum system applied about or to the support surface.
 28. The method ofclaim 25, wherein adhering binder material to the reinforcing materialincludes conditioning the binder material with heat and forcing theconditioned binder material into the stream of reinforcing material. 29.The method of claim 26, wherein said spraying includes creating aheating zone and feeding the adhesive mixture through the heat zone. 30.The method of claim 28, wherein providing a stream of fibrous materialincludes blowing chopped fiberglass.
 31. The method of claim 26, whereinspraying the adhesive mixture includes spraying the mixture onto avertical support surface.
 32. The method of claim 26, wherein sprayingthe adhesive mixture includes spraying the mixture onto a solid surface.33. The method of claim 26, wherein spraying the adhesive mixtureincludes spraying the mixture onto a perforated surface.
 34. The methodof claim 26, wherein spraying the adhesive mixture includes spraying themixture onto the support surface under ambient air conditions.
 35. Apreform formed in accordance with the method of claim
 25. 36. Acomposite structure molded obtained from the preform formed inaccordance with the method of claim
 25. 37. An end effector adapted forconnection to a robot arm for applying a heated adhesive mixture of abinder and a reinforcing fiber to a surface, said effector comprising: aframe support; at least two spaced burners mounted on the frame toproduce respective flames, with the two flames being oriented to heat aregion disposed there between; a nozzle arrangement for dispensing amixed stream of binder and reinforcing fiber into the heated region tocause heating of the mixture. a respective manifold associated with eachof the burners and having an inlet for a cooling medium connectedthereto; and, a respective shield member disposed between each manifoldand an associated burner to minimize interaction between the stream ofcooling medium and the heated region.
 38. The end effector according toclaim 37 connected to a robot arm.
 39. The end effector according toclaim 37 wherein the at least two burners are elongated, aresymmetrically disposed on the frame, extend parallel to one another andare inclined inwardly.
 40. The end effector according to claim 39wherein the manifolds are elongated, are symmetrically disposed on theframe, extend parallel to one another, and extend along the length ofthe associated burners to produce a curtain of cooling medium.
 41. Theend effector according to claim 40 wherein the shields are elongated,are symmetrically disposed on the frame, and extend parallel to oneanother.
 42. The end effector according to claim 41 wherein the nozzlearrangement includes a venture tube mounted on the frame between the twoburners, and having an inlet opening for receiving the reinforcingmaterial at one end and a spray pattern outlet nozzle for the mixedstream at its other end, an inlet port extending into the interior ofthe venture tube for the introduction of a liquid binder, and an airinlet to the interior of the venture for the introduction of a carriergas.
 43. The end effector according to claim 42 wherein the outletnozzle has an elongated shape extending parallel to the extensiondirection of the burners.
 44. The end effector according to claim 43wherein a pair of said venture tubes are provided with their outputnozzles being axially aligned in the extension direction of the burners.45. The end effector according to claim 37 wherein the nozzlearrangement includes at least one venture tube mounted on the framebetween the two burners, and having an inlet opening for receiving thereinforcing material at one end and a spray pattern outlet nozzle forthe mixed stream at its other end, an inlet port extending into theinterior of the venture tube for the introduction of a liquid binder,and an air inlet to the interior of the venture tube for theintroduction of a carrier gas.
 46. The end effector according to claim45 wherein the at least two burners are elongated, are symmetricallydisposed on the frame, extend parallel to one another and are inclinedinwardly; and the outlet nozzle has an elongated shape extendingparallel to the extension direction of the burners.
 47. The end effectoraccording to claim 46 wherein a pair of said venture tubes are providedwith their output nozzles being axially aligned in the extensiondirection of the burners.